steam trapping - an overview

Steam trapping overview

*

The benefits of effective steam trappingSpirax Sarco are focused on helping our customers achieve process efficiency, increased production output and energy savings, and we know the importance of effective steam trap management in achieving this. A healthy steam trap population allows condensate to be removed from the steam system effectively which means it can be re-used. We call this ‘condensate recovery’ and it saves energy and cost in a number of different ways:

Reduced fuel costs Normally, condensate will contain around 25% of the usable energy of the steam from which it came. Returning this to the boiler feedtank can save thousands of pounds per year in energy alone.

Energy saving Condensate returned to the feedtank reduces the need for boiler blowdown, which is used to reduce the concentration of dissolved solids in the boiler. This therefore reduces the energy lost from the boiler during the blowdown process.

Reduced water charges Returning and re-using condensate reduces the requirement for fresh replacement water.

Reduced chemical treatment costs Re-using as much condensate as possible minimises the need for costly chemicals to treat raw water.

Reduced effluent costs In many countries there are restrictions on releasing effluent at elevated temperatures so it must be cooled if discharged which incurs extra costs.

Spirax Sarco are always on hand to advise you about the best ways to manage your steam system and to help ensure you continue to reap these benefits.

spiraxsarco.com

For more information about our steam trapping solutions, or any of our other solutions and services please visit spiraxsarco.com.

3

spiraxsarco.com

Thermodynamic steam trapsMaintaining optimum process performanceThermodynamic steam traps are the best choice for steam mains drainage due to their simplicity, long life and robust construction. With a large condensate capacity for their size, the all stainless steel construction of our thermodynamic traps offer a high degree of resistance to corrosive condensate.

Thermostatic steam trapsUtilising heat energy in condensateFor applications where it would be desirable to make use of the heat in the condensate such as sterilisation, a thermostatic steam trap is an ideal solution as it will not open until the condensate temperature drops below saturated steam temperature. This allows the heat in the condensate to be utilised before it is drained off which in turn reduces flash steam losses and can help to reduce energy costs.

An introduction to steam traps

Mechanical steam trapsMaintaining optimum process performanceMechanical steam traps are ideal for use on process applications where condensate must be removed as soon as it forms, to safeguard against temperature fluctuation which would lead to issues such as product spoilage and inadequate heating. Our mechanical steam trap range is adaptable to all applications where instantaneous removal of condensate is required.

Each steam application has its own steam trap requirements. Selecting the right steam trap for your application could have a significant, positive impact on your process, potentially improving efficiency, reducing energy costs and giving you a safer working environment.

For example: condensate must be removed promptly from a plant where maximum heat transfer is sought at all times. The presence of excess condensate in an item of heat transfer equipment will reduce its efficiency, preventing it from achieving its maximum rated output and may also reduce its service life.

However; in other applications, it may be required to hold back the condensate to extract some of its heat and thus save on steam. Furthermore, by discharging condensate well below steam temperature, flash steam losses can be reduced or avoided altogether.

Spirax Sarco offers a complete range of steam traps to ensure you canselect the perfect trap for your application.

5

s t e a m t r a p p i n g

Steam trap operation Thermodynamic Mechanical Thermostatic

Steamtrap types

Thermodynamic Ball float Inverted bucket

Balanced pressure

Bimetallic

Main features

• Robust design giving excellent resistance to waterhammer and vibration

• Inexpensive

• Positive discharge with tight shut-off

• Discharge condensate close to steam saturation temperature

• High capacity

• Excellent air venting capabilities

• Continuous discharge of condensate for maximum heat transfer

• Will not back-up with condensate

• High capacity

• Robust design

• Near continuous discharge of condensate

• Minimal back-up of condensate

• Utilises sensible heat in the condensate, reducing flash steam losses, which saves energy

• Excellent air venting properties for quick start-up

Typical applications

Mains drainage and all tracing applications.

Some process applications with light loads such as small presses and cylinders

Temperature / pressure controlled applications with fluctuating loads

Temperature / pressure controlled applications with fluctuating loads

• Where condensate back-up can be tolerated or is required in order to remove excess enthalpy, e.g. non-critical tracing

Size DN8 – DN25(¼”– 1”)

DN15 – DN100(½" – 4")

DN15 – DN50(½" – 2")

DN8 – DN25(¼"– 1")

DN8 – DN100(¼"– 4")

Maximum body rating PN250 PN100 and

ASME Class 600 ASME 900 PN40 and ASME Class 300

PN420 and ASME Class 2500

Maximum operating pressure

250 bar g 80 bar g 110 bar g 32 bar g 150 bar g

Spirax Sarco’s steam trap range

t h e r m o d y n a m i c s t e a m t r a p s

How a thermodynamic steam trap works

1. On start-up, incoming pressure raises the disc and cooled condensate, and air is immediately discharged.

2. Hot condensate flowing through the trap releases flash steam. High velocity creates a low pressure area under the disc and draws it towards the seat.

3. At the same time there is a pressure build-up of flash steam in the chamber above the disc which forces it down against the pressure of the incoming condensate until it seats on the inner ring and closes the inlet. The disc also seats on the outer ring and traps pressure in the chamber.

4. Pressure in the chamber is decreased by condensation of the flash steam and the disc is raised. The cycle is then repeated.

1

3

2

4

Features and benefits:

• Positive condensate discharge with clean tight shut-off

• Discharges condensate at very close to steam temperature that ensures maximum plant efficiency

• Just one moving part, a disc, ensures reliable operation and minimal maintenance without having to remove from the line

• Compact and light weight, reducing installation costs

• Hardened disc and seat for long life

• One trap covers a wide range of operating pressures making selection and replacement simple

• Insulating cover for low ambient temperature or wet environments

• Thermodynamic traps can be used on high pressure and superheated steam and are not affected by waterhammer or vibration.

Thermodynamic steam traps

7

MaterialMaximum operating pressure

Connection

SizesRecommended

installationDN8¼"

DN10"

DN15½"

DN20¾"

DN251"

Carbon steel

42 bar g Socket weld TD42S2 TD42S2LC Horizontal

46 bar gScrewed

Socket weldFlanged

TDC46M Horizontal

Stainless steel

10 bar g Screwed TD10 Horizontal

30 bar g SwivelUTD30L UTD30H

(universal connection)Universal

32 bar g Flanged TD32F TD32FLC Horizontal

42 bar g

Butt weld TD3-3 TD3-3TD3-3LC TD3-3 Horizontal

Screwed TD 259TD52M

TD42LCTD42L TD52M

TD42TD42LCTD42HTD42L TD52M

TD52MLC

TD42TD42HTD42LTD52M

TD42HTD42LTD52M

Horizontal

46 bar g Swivel UTDS46M Universal

46 bar gScrewed

Socket weldFlanged

TDS46M Horizontal

Alloy steel

62 bar gScrewed

Socket weld Flanged

TD62M TD62LM Horizontal

250 bar gSocket weld

Butt weld Flanged

TD120M Horizontal

Stainless steel (Clean steam)

10 bar g

Screwed BTD52L Horizontal

Clamp Tube end BTD52L Horizontal

Thermodynamic steam traps - product range

spiraxsarco.com

m e c h a n i c a l s t e a m t r a p s

Ball float mechanical steam trapsBall float (FT) mechanical steam traps have an integral air vent as standard and the options of a manually adjustable needle valve (SLR - steam lock release mechanism) and drain cock tapping, the FT range is adaptable to all applications where ball float traps are recommended and instantaneous removal of condensate is required.

2

43

1

How a ball float steam trap works1. On start-up a thermostatic air vent allows air to bypass the main valve (1) which would otherwise be unable to escape (a condition known as ‘air-binding’).

2. As soon as condensate reaches the trap, the float israised and the lever mechanism opens the main valve.Hot condensate closes the air vent but continues to flowthrough the main valve.

3. When steam arrives the float drops and closes off the main valve, which remains at all times below the water level, ensuring that live steam cannot be passed.

4. As the steam condenses, the float rises allowing condensate to be released.


• Immediate condensate discharge with clean, tight shut-off. No backup of condensate ensures maximum plant efficiency

• Works efficiently on both heavy and light loads with no passage of live steam

• Not affected by wide and sudden fluctuations of pressure or flowrate

• Stainless steel internals that can tolerate corrosive condensate

• Integral air vent to ensure rapid warm-up of plant

• Robust construction to guarantee long life against waterhammer and vibration.

Mechanical steam traps

9

spiraxsarco.com

MaterialMaximumoperatingpressure

Connection

Sizes

InstallationDN15½"

DN20¾"

DN251"

DN321¼"

DN401½"

DN502"

DN803"

DN1004"

Cast iron13 bar g Flanged

FT43 FT43 FT53 FT43 Horizontal

FT43V FT43V FT53V Vertical down

14 bar g Screwed FT14 Horizontal

SG iron

14 bar gScrewed

FT14 Horizontal

FT14V Vertical down

Flanged FT14 Horizontal

21 bar g Screwed FT14HC FT14 Horizontal

32 bar gFlanged FT47

FT57FT47 FT57 Horizontal

Flanged FT47V FT47V Vertical down

ENP coatedSG iron coverandstainless steelbody

14.6 bar gScrewed FTGS14 Horizontal

Flanged FTGS14 Horizontal

17 bar g Screwed FTGS14HC Horizontal

Carbon steel

23 bar g Flanged FTC23 Horizontal

32 bar g

Screwed Socket weld

FTC32 FT450* Horizontal

FTC32V Vertical down

Flanged

FTC32 FT44 FT54

FT44 FT54

FT44 FT54

FT44 FT450* Horizontal

FTC32V FT44V FT54V

FT44V FT54V

FT44V FT54V Vertical down

80 bar g

Socket weld Flanged FTC80 Horizontal

Screwed Socket weld

FlangedFTC62 Horizontal

Stainless steel

23 bar g Flanged FTS23 Horizontal

19 bar gScrewed

Socket weld Flanged

FTS14 Horizontal

FTS14V Vertical down

25.5 bar g Flanged FT46 FT46 Horizontal

32 bar g Swivel UFT32 Universal

65.8 bar gScrewed

Socket weld Flanged

FTS62 Horizontal


4.5 bar ΔP ClampFTS14-4.5 Horizontal

FTS14V-4.5 Vertical down

Ball float steam traps - product range

* not PED approved

Mechanical steam traps

Inverted bucket mechanical steam traps Our inverted bucket steam traps employ a well-proven principle which relies on the difference in density between steam (a vapour) and condensate (a liquid). They have a robust design and incorporate a simple density sensitive bucket and lever mechanism.

m e c h a n i c a l s t e a m t r a p s

How an inverted bucket steam trap works

1. As condensate reaches the trap it forms a watersealinside the body. The weight of the bucket keeps the valveoff its seat. Condensate can then flow around the bottomof the bucket and out of the trap.

2. When steam enters the underside of the bucket it givesit buoyancy and the bucket rises. This positions the levermechanism such that the main valve ‘snaps’ shut due toflow forces.

3. The bucket will lose its buoyancy as the enclosedsteam condenses due to radiation losses and steamescapes through the vent hole. Once this happens theweight of the bucket will pull the valve off its seat and thecycle is then repeated.

4. Any air reaching the trap will also give the bucket buoyancy and close the valve preventing condensate flow. Thesmall vent hole positioned at the top of the bucket will lead air into the top of the trap. Because the vent hole at the top ofthe bucket is small in diameter it will vent air very slowly. Where the venting of air may be a particular problem, this canbe overcome simply by fitting an external air vent in parallel.

1 2

3 4


• Near continuous condensate discharge with tight shut-off. Minimal back-up of condensate ensures maximum plant efficiency

• Deep water-seal to protect against the possibility of steam loss

• Suitable for superheat conditions when fitted with internal inlet check valve

• Simple and robust construction to guarantee long life against waterhammer and vibration

• Stainless steel internals are attached to the cover for ease of maintenance

• Integral strainer (HM, HM34 and SCA models only)

• Optional blowdown valve (only for HM and HM34).

11

spiraxsarco.com

MaterialMaximumoperatingpressure

ConnectionSizes

InstallationDN15½"

DN20¾"

DN251"

DN401½"

DN502"

DN803"

Cast iron

13 bar g Screwed Flanged

S SF Horizontal

14 bar g Screwed Flanged HM Horizontal

22 bar g Screwed Flanged 200 Vertical

Carbon steel

32 bar gScrewed

Socket weld Flanged

HM34 Horizontal

41 bar gScrewed

Socket weld Flanged

SCA Horizontal

116 bar gScrewed

Socket weld Flanged

IBV Series C IBV Series C-LDF2 Vertical

Stainless steel

30 bar g

Screwed Socket weld

Flanged

SIB30 SIB30H Horizontal

Swivel UIB30 UIB30H Universal

60 bar g ScrewedFlanged SIB45 Horizontal

63 bar g Swivel UIB46 Universal

Alloy steel 123 bar gScrewed

Socket weld Flanged

IBV Series Z Vertical

Inverted bucket steam traps - product range

Thermostatic steam traps

How a balanced pressure thermostatic steam trap works 1. On start-up, cold air and condensate enter the trap. As the capsule is also cold, the valve is open and the air and condensate are discharged.

2. The capsule warms up as the condensate approaches steam temperature. Its liquid filling boils, and the resultant vapour pressure acting on the diaphragm pushes the valve head towards the seat, fully closing at the selected discharge temperature before any steam is lost.

3. As the condensate within the trap cools, the vapour filling condenses and the internal capsule pressure falls. The valve reopens, discharges condensate and the cycle repeats.

t h e r m o s t a t i c s t e a m t r a p s


• Condensate is discharged at below steam saturation temperature, utilising sensible heat in the condensate and reducing flash steam losses

• Automatically discharges air and other incondensable gases to aid rapid warm-up of plant

• It automatically adjusts itself to variations of steam pressure up to its maximum operating pressure and can tolerate superheat up to 70°C

• Discharge temperature set by capsule selection – no requirement to adjust on site

• Manufactured using advanced technology to exacting quality standards

• All stainless steel internals extend working life and reduce plant maintenance

• The BPC32 and BPS32 series has a two bolt cover design for ease of maintenance.

2 3

1

13

Balanced pressure thermostatic steam traps - product range

spiraxsarco.com


Connection

SizesRecommended

installationDN8¼"

DN10"

DN15½"

DN20¾"

DN251"

DN401½"

Brass 13 bar g Screwed

BPT13SBPT13US Horizontal

BPT13ABPT13UA Angle

Carbon steel

21 bar g

Screwed BPM21L Horizontal

Socket weld BPM21L Horizontal

32 bar g

Screwed Socket weld

BPC32 BPC32Y Horizontal

Flanged

BPC32 BPC32F BPC32Y

BPC32YF

Horizontal

Stainless steel

21 bar g

Screwed MST21MST21

MST21H TSS21

MST21H Vertical down

Sandwich between flanges

BPW32 Vertical down

30 bar gScrewed

Socket weld Flanged

SBP30 Horizontal

32 bar g

Screwed Socket weld

Flanged

BPS32 BPS32Y Horizontal

Swivel UBP32 Universal


7 bar g

Screwed BTM7 BTS7

BTM7 BTS7 Vertical down

ClampBTM7 BTS7

BTS7.1Vertical down

Tube end BTM7 BTS7 Vertical down

6 bar g Clamp Tube end

BT6-BH BT6-BL Vertical down

t h e r m o s t a t i c s t e a m t r a p s

How a bimetallic thermostatic steam trap works

1. On start-up, the bimetallic element is relaxed and the valve is open. Cooled condensate, plus air, is immediately discharged.

2. Hot condensate flowing through the trap heats the bimetallic element causing it to pull the valve towards the seat.

3. As the hot condensate is discharged and approaches steam saturation temperature the bimetallic element closes the valve. When there is no flow through the trap the condensate surrounding the element cools causing it to relax and the upstream pressure opens the valve. Condensate is discharged and the cycle repeats.


• Condensate is discharged at below steam saturation temperature, utilising sensible heat in the condensate and reducing flash steam losses

• Automatically discharges air and other incondensable gases to aid rapid warm-up of plant

• The bimetal elements can work over a wide range of steam pressures without any need for on-site adjustment

• Resistant to waterhammer and freezing

• The SMC32 series has a two bolt cover design for ease.

1

2 3

Thermostatic steam traps

15


Connection

SizesRecommended

installationDN8¼"

DN10"

DN15½"

DN20¾"

DN251"

DN401½"

DN502"

DN803"

DN1004"

Carbon steel

21 bar gSocket weld

Butt weld Flanged

SP80 SP100 Horizontal

32 bar g

Screwed Socket weld

Butt weld

SMC32 SMC32Y Horizontal

Flanged

SMC32 SMC32F SMC32Y

SMC32YF

Horizontal

45 bar g

Screwed Socket weld

Butt weld Flanged

HP45 Horizontal

Stainless steel

17 bar g Screwed T3 Vertical down

21 bar g Swivel USM21 Universal

32 bar g

Swivel USM32 Universal

Screwed Socket weld

FlangedPBX Horizontal

Alloy steel

45 bar g

Screwed Socket weld

Butt weld Flanged

SM45 Horizontal

80 bar g

Socket weld Butt weld

SM80 Horizontal

100 bar g SM100 Horizontal

150 bar g SM150 Horizontal

spiraxsarco.com

Bimetallic thermostatic steam traps - product range


Key features:

• A simple two-bolt connector design allows quick and simple maintenance of a steam trap - Reducing system downtime and maintenance costs compared to traditional trapping stations

• Single permanent in-line component for ease of specification and installation

• Prefabricated construction minimises on-site fabrication and the welded joints eliminate potential leak paths

• All stainless steel construction for maximum system life.

PC10HP up to 62 bar g*

PC20up to 32 bar g

PC30 seriesup to 62 bar g*


Reducing production running costs

Spirax Sarco can supply fabricated steam trap stations and a range of ‘quick-fit’ solutions that will allow rapid steam trap replacement and significantly reduce labour costs.

UTD30L and UTD30Hup to 30 bar g

Thermodynamic steam trap

UTDS46Mup to 46 bar g*


The pipeline connectors require 2 bolts for connection with a steam trap.

Universal steam traps for use with pipeline connectors for a ‘quick fit’.

Pipeline connectors

17

STS17.2up to 17.5 bar g

Steam trapping station

spiraxsarco.com

Downstream isolation valve

Upstream isolation valve

Check valve

Pipeline connector with an integral strainer screen





UFT32up to 32 bar g

Ball float steam trap

UIB30 / UIB30H up to 30 bar g

UIB45up to 63 bar g*

Inverted bucket steam trap

UBP32up to 32 bar g

Balanced pressure steam trap

USM21 up to 21 bar g

USM32up to 32 bar g

Bimetallic steam trap

UTDS46Mup to 46 bar g*


The pipeline connectors require 2 bolts for connection with a steam trap.

Universal steam traps for use with pipeline connectors for a ‘quick fit’.

Steam trapping station

*subject to limitation of pipeline connector

* Subject to pressure limits of trap selected

Steam tracing using our compact dual duty manifold

Key features:

• Minimises on-site fabrication and testing

• Lower cost than conventional welded design

• Shortens project lead times

• Space saving with standardised design

• Lightweight to support and easy to install with optional mounting kit

• Easy to maintain

• Optional insulation jacket for energy conservation.

Steam main

Condensate main

To tracer lines From tracer lines

Product line

MSC steam distribution manifold

MSC condensate collection manifold

We will advise on the best steam trap type for

your requirements


Steam tracing is used principally to maintain a reasonable product temperature and viscosity in order to simplify pumping, avoid freezing, solidification and stagnation. Although the rates of condensate are relatively small, trap populations will be large since all tracer lines should be individually trapped. For ease of design and layout, the condensate from the traps is collected in a manifold. The steam to the tracers can be distributed utilising a similar manifold arrangement.

Our forged MSC series manifold minimises on-site fabrication and testing.

Manifold typeNumber of tracer

connections

DN Tracer connectionsEN 10204 3.1.B

certification

Options

15 20 BSP NPT SW Insulation jacket

Mounting kit

MSC04 4 ● ● ● ● ● Standard ● ●MSC08 8 ● ● ● ● ● Standard ● ●MSC12 12 ● ● ● ● ● Standard ● ●


The duty of a steam trap is to discharge condensate

while retaining live steam in the system. This ensures

your steam system is able to operate efficiently, without

the detrimental effects of unwanted condensate -

essential in temperature critical applications.

Condensate in the system can lead to a number of

issues such as:

- Poor heat transfer

- Damage to system and process equipment

- Poor quality or wasted product

Selecting the right steam trapping solution helps to

avoid these problems, whilst at the same time allowing

the condensate to be recovered. Information on the

significant benefits of recovering condensate can be

found at the back of this brochure.

How can Spirax Sarco help you?We’ve been in the business of steam solutions for over 100 years and with our exceptional team of specialists, we take the time to understand your needs and work with you to find the most effective steam trapping solutions for your applications.

Our aim is to help you meet your sustainability and efficiency goals by ensuring your steam system operates at its optimum level at all times. Effective steam trapping is a key factor in achieving this objective.

Make your steam system safe, efficient and sustainable

19

Typical applications for steam traps

Steam main

Condensate main

Mains drainage

Hot plate process

Steam in

Condensate out Condensate in

Hotplates

Vulcaniser application

Steam to jacket

Steam into

chamber

Condensatefrom jacket to condensate system

Condensate from chamber to waste

spiraxsarco.com

Condensate out

Steam outSteam in

Turbine drainage

Drainage of a separator

Condensate

Steam

Condensate

Secondary flow

Process equipment

Air vent

Condensate

spiraxsarco.com

*

* Manufacturing sites

BelgiumCzech RepublicDenmarkEgyptFinlandFranceGermanyIrelandItalyMiddle EastNorway

EMEA

AustraliaChinaIndiaIndonesia Japan MalaysiaNew Zealand

Asia Pacific

Netherlands Poland PortugalRussiaSouth AfricaSpainSwedenSwitzerlandTurkeyUK

Philippines SingaporeSouth KoreaTaiwanThailandVietnam

Argentina BrazilCanadaChile

AmericasColombiaMexicoPeru USA*

*

*

*

**

Operating Companies Sales Offices

AustriaHungaryIvory CoastJordanKazakhstanKenyaRomaniaSlovak RepublicUkraine

EMEA

CambodiaHong KongMyanmar

Asia Pacific

Distributors

AlgeriaBahrainBulgariaCameroonCroatiaCyprusEthiopiaEstoniaGhanaGreece

EMEAMoroccoNamibiaNigeriaOmanQatarSaudi ArabiaSloveniaSudan

IcelandIsraelKuwaitLatviaLebanonLithuaniaMadagascarMalawiMaltaMauritius

Bangladesh

Asia Pacific

AmericasBoliviaDominican RepublicEcuadorEl Salvador

NicaraguaParaguay Trinidad and TobagoUruguay

Guatemala HondurasJamaicaNetherland Antilles

Fiji

*

Pakistan

Costa RicaPanama

Americas

*

SB-GST-33 ST Issue 5

Spirax-Sarco Limited, Charlton House, Cheltenham, Gloucestershire, GL53 8ER, UK

T +44 (0)1242 521361 F +44 (0)1242 573342

E [email protected]

Spirax-Sarco ensures that it is fully compliant with all United Nations, European Union and U.S. sanctions in relation to the supply of its products and services.

In relation to the manufacture of our products, we ensure we do not use conflict minerals.

© Copyright 2016 Spirax Sarco is a registered trademark of Spirax-Sarco Limited

steam trapping - an overview

Documents

Transcript of steam trapping - an overview